Lens-diaphragm-controlling device for kinematographic apparatus.



E. A. IVATTS.

LENS DIAPHRAGM CONTROLLING DEVICE FOR KINEMATOGBAPHIO APPARATUS.

APPLICATION FILED SEPT. 1, 1910.

1,029,997, Patented June 18, 1912.

Fig.2 Fig.5

Wilffiessas: I U fnvenffir;

ERNEST ALBERT .IVATTS,

OF PARIS, FRANCE, ASSIGNOR T0 SOCIETY COMPAGIEE] GENERALE DE PHONOGRAPI-IES, CINEMATOGRAPHES ET APPAREILS DE FREQ!- SION, OF PARIS, FRANCE.

LENS-DIAPHRAGM CONTROLLING DEVICE FOR KINEMATOGRAPHIC APPARATUS.

Specification of Letters Patent. Application filed September 1, 1910.Serial No.

Patented J line 18, 1912.

To all whom, it may concern:

Be it known that I, ERNEST ALBERT.

IvATTs, citizen of Great Britain, residing at Paris, in the Departmentof the Seine,

rance, have invented certain new and useful Improvements inLens-Diaphragm-Controlling Devices for Kinematographic Apparatus, ofwhich the following is-a specification. p

This invention refers to a mechanical device for use with photographickinematographic apparatus whereby the operator is enabled automaticallyto effect the progressive appearance of one subject simultane- 'ouslywith the progressive disappearance of another subject, so that whenprojecting the picture, the image representing the new subject graduallyincreases in intensity until it acquires its full intensity whereas theold image correspondingly decreases in intensity until itcompletely'disappears. This operation may affect the whole of the imageor only a portion of the same. This operation is actually effected bymanipulating by hand the diaphragm of the lens. It comprises twodistinct phases:

The first phase or phase of disappear ame.-Atthe monientin which theimage should commence to loose its intensity, that is to say todisappear, manipulate by hand as regularly as possible the diaphragm ofthe lens so as to completely close this diaphragm at the end of acertain period of time, corresponding in practice to a number ofrevolutions given to the crank by means of which the operator rotatesthe mechanism of his apparatus. When the diaphragm is completely closed,the operator stops his apparatus and turns back the portion of the filmwhich has passed in front of the lens during the period of the closingof the diaphragm. In practice this is effected by turning back the crankthrough the same number of revolutions through which it was turnedforward.

Second phase 01? the phase 0;" appearance.The first phase beingterminated and during'the interruption in the-photographic operations,the subjects which it is desired now to photograph are placed inposition on the stage of the theater. ls hen everything is ready, theoperator again actuates his apparatus at the same time progressivelyopening the diaphragm-'- the lens the operator begins to during the samenumber of revolutions of the crank as previously so that at the-end l aperiod of time determined for the operating, the diaphragm will beopened. to same degree as at the beginning. The photographic operationsare then continued in the usual way. It will be easily understood thatunder these conditions this progressive interchange of two subjects is adelicate operation entirely dependent on the denterity of the operator.In practice it is very difiicult to avoid false photographic shades andthe appearance of the subjects instead ofbeing produced graduallyiseffected in a jerky manner. The mechanical device forming the object ofthe present invention is for the purpose of avoiding these drawbacks byautomatically effecting the gradual opening and closing of the diaphragmor any other type of obturat-or. It further more permits of effectingthis gradual change of subjects with any initial position whatever ofthe diaphragm, dependent on the conditions of light, the operationalways being effected in the same period of time determined beforehandaccording to requirements.

I shall now describe this invention with reference to the accompanyingdrawings in which- Figure 1 shows a front view of the whole of thedevice. Figs. 2, 3 and 4 are views of the same profile of the cam forvarious positions on its shaft. Figs. 5, 6' and 7 are views of variousprofiles of the cam for the same position on its shaft.

Referringto-Fig. 1 it may be seen that the deviceis driven by an endlessscrew 1 keyed to the shaft 2 controlling the parts of the apparatus.Owing mentthe rotary speed of the parts thus actuated will depend on thenumber of images photographed. A cog wheel 3 axially sliding along ashaft- 4, although the rotary movement of the said shaft can be made tomesh when desired with the endless .screw 1, for example by means of aknob or any other device actuated by the operator at the desired moment.A cam is also mounted in similar manner on the said shaft 4 along whichit can slide although dependent on the rotary movement of the same. Thisearn 5 is preferably formed by a truncated'cone to this arrange-.

with circular.

dependent on base, of which'thc one rectilincal generating line 6 isparallel to the rotary axis of the shaft 4. It is evident that for thesame purpose a cam of diiferent construction might ialso be. employed.Thus the bases of the truncated'cone instead of: being circular might beelliptical or ovoid so as to permit, if necessary, of effecting theclosing of the obturating diaphragm, not proportionally to the diameterof the same but proportionally to the'a-rea of the aperture in thisdiaphragm and consequently to the quantity of light passing on to thefilm. Instead of being "in the form of a truncated cone with rectilinealgenerating lines, the cam may be of any other. .shape provided that itpossesses a recti-lineal generating line parallel. to the axis ofrotation, that is to say to the shaft 4. This cam 5, whatever may be itsconstruction, acts on the arm of a lever 7 pivoted at 8. By theintermediation of a connecting rod 10 this lever actuates a lever 9controlling the movable rim 11 of the' obturating diaphragm of a lens 12arranged in a tube 13. A suitably arranged spring 13 assures the contactof the edge of the lever i 7 on the cam 5. According to the position ofthis latter the diaphragm of the lens 12 will be either open or closedor in any other interm diate position as shown for example inthe -igs. 2to 7 The diaphragm is closed when the lever 7 rests on the small base 5causing the cam of the cam 5 or when it rests on the part leasteccentricall situated with respect to the shaft 4, that 18 to say at anypoint along the generating line 6. The diaphragm is fully opened whenthe lever 7 rests on the large base and'on the most eccentric portionsof" the cams; it. is partly open when the lever 7 occupies anintermediate. position on the eccentric portion between the large andthe small base.

As may beseen from Figs. 2, 3 and 4 by moving the cam 5 along the shaft4, the profile remaining the same, one passes gradtially from the openposition of the diaphragm, to the closed position.

As may be seen from Figs. 5, 6 and 7 at Whatever point the lever 7-rests on the cam 5, one-passes gradually during the first half of therotation from the open to the closed position and vice versa during thesecond half of the rotation.

From what precedes it may be seen that the adjustment of the degree ofopening of the diaphragm of the lens 12, is efiected by 5 to slide alongits shaft 4 by means of suitable actuating mechanism, for example ,by'--means of alever and an opposing spring 14.

With this device in order to obtain the progressive interchange ofsubjects, the op erator while continuing to operate the crank with onehand presses at the desired moment on the knob or button 15 so as tocause the cog-wheel 3 to mesh with the endless screw 1 of the shaft-2.At the end of a certain number of revolutions the operator releases thebutton thus stopping the work ing of the device which has effected theclosing of the diaphragm of the lens, owing to the first half rotationof the cam The cam 5 is then intho position represented in Fig. 7 andthe lever 7 is at the extreme left,

as is also the connecting rod 10 and lever or arm 9. The operatorcompletes the interchanging operation by pressing a second time on thebutton 15 during a number of revolutions equal to the previous number ofrevolutions. At this moment the second half rotation of the cam 5 hasbrought back the latter to its initial position and consequently alsobrought back the diaphragm of thelens 12 into its original openposition; the lever. 7, and rods 9 and 10 being at the extreme right.

It is evident that modifications and improvements may be introduced inthis de vice without in any way affecting the essential features of theinvention.

Having now particularly described and ascertained the nature of thissaid invention and in what manner the same is to be performed, I declarethat what I claim is:

1. In a kinematographic apparatus, the combination of a lens-diaphragmwith an automatic controlling device therefor, said device comprising adriving member and a driven member, mechanism for operatively connectingsaid members, said. mechanism including engageable anddisengageableparts, acam carried by said driven member, and meansactuated by said cam for opening and closing said lens-diaphragm.

2. In a kinematographic apparatus, the combination of a lens-diaphragmwith an automatic controlling device therefor, said device comprising adriving member and a driven member, mechanism for operatively connectingsaid members, said mechanism including an engageable and disengageablegear and screw, a cam carried by said driven member and a lever actuatedby said cam for opening and closing saidlensdiaphragm.

3. In a kinematographic apparatus, combination of a lens-diaphragm withan automatic controlling device therefor, said device "comprising adriving shaft and a driven shaft, a gear on said driven shaft and anendless screw on said driving shaft, said gear and screw beingengageable and disengageable, a cam shaped part carried by said drivenshaft having a portion of the operative face thereof substantially inparallelism with said driven shaft and having another portibn of saidface inclined to the axis of sa1d shaft, and a-lens-diaphragmcontrolling part actuated by said cam shaped part, one ofv said partsbeing laterally the dlsplaceable with respect to the other of saidparts, the amount of displacement determining the maximum opening of thediaphragm during a determined rotary movement of the driven shaft.

4. In a. kinematographic apparatus, the combination of a lens-diaphragmwith an automatic controllingdevice therefor, said device comprising-adrlvmg member and a shaped part, one of said mechanism portion of saidface at an angle to said first mentioned portion, and a lens diaphragmcontrolling part actuated by said camsaid parts being laterallydisplaceable with respect to the other of said parts, the amount ofdisplacement determining the maximum opening of the diaphragm during adetermined movement .of the driven member.

Intestimony whereof; aflix my ture in presence of two witnesses.

ERNEST ALBERT WAT-Ts.

Witnesses:

v HENRY DANTER, LUCIEN CRESPIN.

signa- Copies of this patent may be obtained for five cents each, byaddressing the "Commissioner of Patents,

Washington, D. C.

